ACL matching on URLs

Hi all,
I'm looking for the best approach for matching the first part of a URL in ACLs. Some examples of the types of URLs include:

Backend 1 (application context-path = /web) http://hostname:port/web
http://hostname:port/web/form.html

Backend 2 (application context-path = /webservices) http://hostname:port/webservices/serviceA http://hostname:port/webservices/serviceB

The following approach for ACLs would only work if the ACL that matches /webservices comes before the one for /web. Ideally I don't want to have to enforce this type of constraint as we have 70+ URL patterns for one frontend and this type of restriction could be error-prone as more patterns are added over time.

Won't work
acl backend1_acl path_beg /web
acl backend2_acl path_beg /webservices

use_backend1 if backend1_acl
use_backend2 if backend2_acl

Will work
acl backend1_acl path_beg /web
acl backend2_acl path_beg /webservices

use_backend2 if backend2_acl
use_backend1 if backend1_acl

Is there some straight forward solution that I'm missing? Perhaps a regex is the only way to enforce a concrete rule? Any suggestions?

Many thanks for your help.

Regards,
Eoin

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